( mbool 
   (
      (
         ( "begin of time"  "2003-11-20-07:00"  TRUE  FALSE ) TRUE )
      (
         ( "2003-11-20-07:00"  "2003-11-20-08:50"  TRUE  FALSE ) FALSE )
      (
         ( "2003-11-20-08:50"  "end of time"  TRUE  TRUE ) TRUE )))